Underfired regenerative coke oven



Patented May 7, 1940 UNITED STATES PATENT OFFICE 2,199,518 UNDERFIBED REGENEBATIV COKE OVEN Walter Stckel, Bochum, Germany, asslgnor to' Otto-Wilputte Ovenbouw Mii. (Otto-Wilputte 0ven ('Jonstruction Company) N.

V., The

Hague, Netherlands. a corporation of the Netherlands Application July '1, 1939, Serial No. 283,150 In Germany November 14, 1938 s claims. (c1. zoe-A241) The present invention relates to coke ovens and particularly to horizontal underflred coke ovens having horizontal regenerators extending parallel 'to the horizontally elongated coking length, a combustible agent to be preheated in the regenerator. The combustible agent so supplied may be a lean fuel gas, or combustion air. In so-called combination ovens, some of the distribution pipes may supply combustion air only, while other distribution pipes may supply either lean gas or combustion air, accordingly as the oven is heated by the combustion of preheated lean fuel gas, or by the combustion of a rich fuel gas which is not preheated.

The object of the present invention is to provide a simple and eflective method of,\ and means for preventing the flow of waste heating gases through such metal distribution pipes, during the periods in which the lregenerators respectively associated with the pipes, are serving as oi!" regenerators." During each period in which a regenerator is serving as Van "oiT regenerator, a distribution pipe connected to the regenerator at points distributed along its-length provides a bypass or flow path for some of the waste gases flowing through the regenerator to the outlet therefrom then connected to a stack or other exhauster.j

The waste gases ordinarily include sulphur 4and other constituents which have high dew points, and' form condensateswhich will corrode the metallic-distribution pipes if allowed to come in contact therewith. The dew points of some of the constituents forming corrosive condensates are higher than the distribution pipe wall temperatures even when the latter are imbeddedv in the masonry at the bottom of the battery, and have somewhat higher temperatures than they do when in their more usual location within the subway space beneath the deck or reinforced concrete slab on which the coke oven brickwork is usually carried.

In accordance with the present invention,

waste gases are kept outof each of the diflerent'- distribution pipes during the period in which it is not supplying a combustible agent to the corresponding regenerator for preheating therein,-

by then passing a non-injurious'gaseous iiuid', ordinarily air, into the pipe, so as -to maintain a slow now therethrough out of the pipe and 'into the regenerator through each of the con- `valve associated with a distribution pipe, the

nections to the latter from the pipe. Waste gases may be thus kept out of the pipe by an amount oi air or other protective iluid flowing through the pipe, which is not large enough to significantly increase the load on" the stack 'or other 'l means employed to withdraw waste gases from the regenerators. Y

The various features of novelty which characterize the present invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages, and specific objects attained by its use,l reference should be had to the accomnying drawings and descriptive matter in ch I have illustrated and described preferred 'forms of embodiment of the invention.

' Oi.' the drawings:

Fig. 1 is a partial vertical transverse section through a horizontal underilred coke oven of conventional design;

Fig. 2 is a' partial section on the line 2,-2 of l; Fig. .3 is a partial section through a supply section being taken on the line 3--8 of Fig. l; Fig. 4 is a section taken similarly to Fig. 1 illustrating a modiiied form of the invention;

Fig. 5 is a partial section on the line 5 5 o! Fig. 4; and e Fig. 8 is a section on the line B-t of Fig. 4

through one of the distribution valves shown in Figs. 4 and 5.

In Figs.' l1-il of the drawings, I have lillustrated the use of the present invention in an underfired coke oven battery of the most usual type com-- prising horizontal elongated coking chambers I which extend transversely of the battery, and alternate with similarly extending heating walls. The latter are formed with vertical combustion ilues 2, each of which is connected at its lower end by separate channels 8 to a regenerator l and to a regenerator 1. Each regenerator -1 is used to preheat combustion air, but the regenerators 8 may be used to prehea't lean fuel gas. As shown, there are two regenerators 'I between each two adjacent regenerators 6, each of the latter being directly beneath a corresponding coking chamber. I, and connected to flues 2in' each .of the two heating walls at opposite sides of said coking chamber. Each regenerator 'I is cwoarlnected only to fiues 2, in a single heating Asthose skilled in the art will understand,

theregenerator arrangement illustrated in Figs. I y

1 and 2 is of the character customarily employed in the most usual type of underfired coke ovens, in which the vertical heating ilues 2 are connected at their upper end to form so-called twin, or hairpin iiues. each of the regenerator chambers 6 and I may extend from one side of the battery to the other, though, as those skilled in the art will understand, in such ovens, as well as in other known forms of coke ovens with which the invention may be used with advantage, each regenerator may have alength which is a fraction only of the length of the oven chamber, and may be arranged in end to end relation with other regenerators of similar length.

Each of the ues 2 is adapted to serve alternately as an upow flue, in which fuel gas and combustion air supplied to the lower end of the flue, ignite and burn, during regular periods which alternate with similar periods inv which the nue serves as a down iiow flue receiving burnt or burning gases from some other flue or ues 2 then serving as upow flues. The fuel gas supplied to each ue 2 may be a rich fuel gas which does not require preheating, and which, is supplied as shown, through vertical channels 3 in the subjacent regenerator division walls from distribution pipes 4 and 5. The pipes 4 being connected to a set of flues 2, which serve as ignition flues during periods alternating with those in which the remaining iiues' receive rich fuel gas from the pipes 5 and serves as ignition ues.

Beneath each regenerator 6 is a corresponding k sole channel 9, and beneath each regenerator 1' is a corresponding sole channel I0, each regenerator being` in fre'e communication all along its length with the corresponding sole channel; The sole channels 9 and I 0 areconnected by corresponding reversing valves I I at one side of the battery, or preferably and as shown at each side of the battery, to a corresponding flue or duct I2, which extends longitudinally of the battery, and leads to a chimney or other Waste gas exhausting means. ods in which the corresponding regenerator is serving as an olf regenerator to permit the waste gases then iiowing from the iiues 2 to and through the regenerator. to pass into the corresponding flue I2. During each period in which a regenerator is serving as an on regenerator, each corresponding valve I I closes communication between the corresponding sole channel, 9 or I0,

and the adjacent waste heat flue I2. Each valve I I is formed with an air-inlet closed by a damper or flap valve II', which is opened to permit atmospheric air to pass into the corresponding regenerator. when the latter is used in preheating combustion air, but is closed at other times.

In the construction shown in Figs. 1, 2 and 3. each regenerator 6 when used'in preheating lean fuel gas is supplied with such gas from a fuel gas supply main I3 through a corresponding valve I4 and metal horizontal distribution pipe I5, and its lateral outlet branches I5. 'I'he main I3 extends longitudinally of"the battery adjacent one side of the latter, and each distribution pipe I5 extends transversely of the battery and is located in the upper portion of the subway space, immediately beneath the deck or supporting platform I6 on which the coke oven brickwork is carried. The delivery branches I5' of each pipe I5 extend through openings in the deck 'I6 and into vertical passages in the bottom wall of the corresponding regenerator sole channel S so as to deliver gas to With such heating flues,

Each valve II is'opened during the perithe latter at a plurality of points distributed along the length of the sole channel. .The gas flow through each pipe I5 may be regulated by means of a corresponding obturator or other regulating device II, which is accessible for regulation through a corresponding opening formed in the underside of the pipe I5 and normally closed by a removable cap or plug member IB.

As shown, each valve I4 vcomprises a casing in which is mounted a rotatable valve member |48. 'Ihe latter is formed with a through passage I4b, which when vertically disposed, passes gas from the supply main I3 to the corresponding distribution pipe I5. When rotated into the position in which the passage I4b is horizontal as shown in Fig. 3, the valve member I4 prevents the outflow of gas from the main I3 through the connection of which the valve forms -a part. The valve member I4 may be turned between the position shown in Fig. 3, and'that in which the passage I4h is vertical, by a valve operating arm I4', adapted to be periodically oscillated by the usual reversing valve gear (not shown) provided in such a coke oven battery.

For the purposes of the present invention, the casing of the valve I4 is formed with an air inlet port I4", which, when the valve member is in the position shown in Fig. 3, is in register with one end of the passage I4b. Atmospheric air may be drawn through the inlet I4" into the passage I4b and thence into the pipe I 5 through a. small passage or port I4c formed in the upper wall of the valve passage I 4b, when the valve member I4EL is in the position shown in Fig. 3.

In the normal operation of the apparatus shown in Figs. 1, 2 and 3, when a regenerator 6 is preheating lean gas supplied thereto through the corresponding distribution pipe I5, the-two immediately adjacent regenerators 'I are employed in preheating combustion air. The said regenerator 6 and the two adjacent regenerators 1, form a regenerator unit which then supplies preheated combustion air and fuel gas to the upburning iiues in the two heating walls at opposite sides of the-coking chamber I directly above the regenerator 6. The other nues 2 in the two heating walls then serve as down iiow iiues and discharge gases through the corresponding channels 8,

suitably small port I4, enough air may be supplied to the pipe I5 to insure that air will ow upward through each of the branch outlet pipes I5 and thereby prevent heating gases from flowing downwardinto the pipe I5 through any of the branches I5'.

As those skilled in the art will understand, the general principles of the present invention may be used with advantage in connection with various types of regenerator coke ovens other than that shown,= in Figs. 1 and 2. For example, they may be ufd in-an oven of the typev shown inv Figs. 4, 5? and 6, in which the combustible agent preheated in regenerators 6A and 'IA extending' transvegsely of the battery, is supplied to the lower ortion of each regenerator, at points distr'i'lduted along its length, through` distributed outlet connectionsfrom a corresponding pipe 2| or 22, extending transversely of the battery and imbedded in a masonry layer 2li interposed between the coke oven brickwork proper, and the supporting deck I8 of an underflred battery. As shown, also, the rich fuel distribution pipes 23 are also imbedded in the masonry layer 20.

As shown in Fig. 4, each distribution pipe 2l is connected at one end through a valve IIA to an adjustment into its open and back into its closed position at the beginning and end, respectively, of each reversal period in which the corresponding regenerator is an on regenerator. When a regenerator 6A is used in preheating combusair main 2I extending longitudinally of the battery, and containing air at a pressure somewhat vide a suitably restricted passage for the flow of enough air from the main 2I into the distribution pipev 2 I, to prevent the passage of waste gas into said pipe during the periods in which the corretion air, the corresponding valve IIC may be maintained continuously in its closed position, and lto this end may then be disconnected from the battery reversing gear.

The rich gas distribution pipe23 shown in Figs. 4' and 5 is adapted to receive rich fuel gas from a supply main 21 extending longitudinally of the battery, during thereversal periods in which the corresponding reversing valve 28 is open. During the reversal periods in which the valve 28 is closed, the, other end of the pipe 23 maybe connected to the air distribution main 2I by adjustment of a corresponding valve IIC.

' so thatthe distribution pipe 21 may then receive sponding regenerator 'IA is serving as an oil`" tribution pipes exposed as shown in Figs. 1 and2,

and in some cases are quite' high enough to eliminate serious risk of deformation of corrosive I -condensates within the pipes.

Each distribution pipe 22 and 23 supplying combustible agent to a regenerator 6A vis also connected at one end to the air main 2I, through valves IIB and IIC. The valve IIC may be a simple valve adjustable between one position in which it closes communication between the main 2I and the distribution pipe 23 and a second or open position in which it does not obstruct communication between'the main and distribution pipe. The valve IIB may be identical inconstruction with the valve IIA, and when the regenerators are all used in preheating combustion air, each valve IIB as well as each valve IIA may be operated by the usual battery reversing gear. to pass air from the main 2I to each of the distribution pipes 2l and 22 during each period in which the corresponding regenerator` is an on regenerator, and during the alternate off periods, the said valve IIA or IIB is adjusted into the position in which air passes at a suitably restrictedY rate from the main 2I to the corresponding distribution pipe, through the small ports IIc and IId. When a regenerator 6A is thus used in preheatingair,`the corresponding valve IIC may be continuously open, but when a regenerator 6A is used in preheating lean gas, its valve IIC is connected to the battery reversing gear, for adjustment to permit or prevent air ow y from the main 2I to the regenerator, accordingly as the latter is serving as an on, or as an olif regenerator. l

When a regenerator GAis used to preheat lean fuel gas, the latter is supplied to the regenerator during its on periods of operation, from a lean gas supply main 25 extending longitudinally of decarbonizing air to burn out graphite deposits in the oven brickwork passages through which rich fuel gas is supplied to the combustion nues.

The outlet connections distributed along the length of the pipe 2|, are formed by .vertical pipes 30, each Welded to the pipe 2| at the margin of registering openings in the walls of the two pipes and through which the two pipes are in free communication. As shown, each pipe 30 has its upper end extending into a channel 3| formed in the coke oven brickwork and opening laterally into the corresponding regenerator 1A, immediately above the top of the corresponding sole channel IIIA. As shown. the regenerator space is separated from the sole channel by a perforated member 32, which may be formed of ceramic material.

The outiiow from the lpipe 2l into, and upward through each pipe 30, is regulatedby an obturator I1, shown as comprising a globular upper end portion centrally disposed in and throttling the portion of the pipe 30 above its connection to the pipe 2I.- 'Ihe obturator I1 has a rod-like body portion extending down' through the pipe 30 and supported on a c ap the battery at the opposite side of the latter i from the main 2I. The main 25-is connected to 'the adjacent end of each distribution pipe 22 through a corresponding valve 26. When lean gas is being preheated and burned each valve 28 is connected to the battery reversing gear for cap I8 are below the underside of'the supporting deck I6. By replacing each obturator I1 by another including a globular portion of different size the flow capacity of the corresponding outlet connection 30, may be suitably regulated.

Each distribution pipe 22 is adapted to deliver air or combustion gas tolthe corresponding regenerator 6A through connections including pipes 30 and passages 3l arranged and adjustable as are the connections to the regenerator 'IA from the pipe 2l. As shown, also, the rich gas distribution pipe 28 is provided with outlet cori-v nections comprising vertical pipes, connected to the distribution pipe 23, as the pipes 30 are connected to the distribution pipes 2I land 22.`

Each of the pipes 33 includes an-ob'turator I'I, and has its upper end extending into a brickwork passage leadin'g upward to the corresponding The reversingvvalve IIA through which 'the' regenerator sole channels IIIA are connected to the stack, may be like the reversing valves Il' though none of them need include a damper controlled air inlet..

Except for the provisions shown for passing air into each of the distribution pipes 2| and 22 during the periods in which the corresponding regenerator is serving as an off regenerator, the special features of construction and arrangement shown in Figs. 4 and 5 form no part of the present invention. but have been shown and described for the vpurpose of illustrating the adaptability o! the invention claimed herein for use in coke ovens of various; types.

While in accordance with the provisions of the statutes, I have illustrated and described the best forms of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set forth in the appended claims and that in some cases certain features of my invention may be used to advantage without a corresponding use of other features.

Having now 'described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In the operation of an underred regenerative coke oven including an elongated regenerator and in which a combustible agent tobe preheated in each such regenerator is supplied thereto through a metal pipe alongside the regenerator and having outlets connected to the latter at points distributed along its length and including means for withdrawing waste gases from said regenerator at its end, the method of excluding waste gases from said metal pipe during periods in which waste gas. is being withdrawn from the regenerator, which consists in then passing a non-injurious gas through said pipe and its outlets into the regenerator.

2. An underred regenerative coke oven battery, comprising in combination an elongated regenerator extending transversely' of the battery, means forwithdrawing waste gas from the regenerator at its end, means for supplying a combustible agent to be preheated to said regenerator comprising a metallic distribution pipe alongside the regenerator and outlet connections from said pipe to the regenerator distributed transversely of the battery and means for passing a non-injurious gas into said regenerator through said pipe and outlet connections during periods in which waste gases are being with drawn from the regenerator by the rst mentioned means whereby the passage ofthe waste.

gases into the distribution pipe is prevented.

3. A coke oven battery as speciiiedin claim 1, in which the means for passinga non-injurious gas through the regenerator into the distribution pipe comprises a valve connected to said pipe and through which when opened air may be drawn from the atmosphere by the rst mentioned means.

WALTER STCKEL. 

